Safety device



Sept. 3, 1946. I s M, UDALE ETAL 2,407,116

' SAFETY DEVICE I Filed oct. 1e, 1944 2 sheawfshwt 1v Jaf/ 57 y INVENTOR v BY Y d Il" 55 ATroRNEY Sept-3, 1946- A s. M; UDALE E-rAL 2,407,116

"sAFETYpEvICE Filed oct; 1s, 1944 v alsngets-sheetvz mvENToR/l/ l ATTORNEY Patented Sept. 3, 1946 SAFETY DEVICE -Stanley M. Udale and Wynton R. Buick, Detroit, Mich., assignors to George M. Holley and Earl Holley Application October 16, 1944, Serial No. 558,917

The object of this invention is to protect a marine engine from excessive speed and the resulting excessive supercharger pressure. Specically, when a boat is traveling fast in a rough sea, rough enough to raise the propeller out of the water, the engine which drives the boat has a tendency to race, and dangerous speeds and supercharger pressures naturally result.

To prevent this, it is customary to interrupt the electric circuit of the engine ignition by means of a centrifugal governor, but when the ignition circuit is restored, which happens immediately after the speed has been reduced, the engine lires into the exhaust passages. These are full of explosive mixture, and the resulting explosion in these exhaust passages is very trying to the nervous system and is almost as bad for the engine and its accessories. Noise is most objectionable for other reasons. The sudden resumption of power imposes a shock on the engine and transmission. If the power is interrupted, the power can be restored after a few seconds or even minutes, as the propeller will continue to rotate and theengine will not stall for a considerable period of time due to the speed of the boat and the reaction of the propeller with the Water through which the boat is traveling.

The object of this invention therefore is to interrupt the ignition and the fuel flow at excessive speeds for a sufficient period of time to prevent any explosions in the exhaust pipes. This object is alternatively achieved by positively locking the ignition switch in the open position and positively closing a flow control deviceto prevent the l ilow of fuel to the fiuel now of the nozzle and thus compelling the operator'in order to restart f the engine, to positively unlock the fuel iiow control device and to replace the ignition switch in the operative position. This gives the operator an opportunity to close the throttle before restarting. Thus a period of high suction follows a period of excessive speed which protects the engine by increasing the lubrication of the pistons. The closure of the throttle, when the engine is rotating at any considerablespeed. causes a suction in the cylinder which causes oil to be drawn up the cylinder walls, which thus lubricates the pistons.

Figure 1 shows diagrammatically the preferred form of our invention applied to the standard marine carburetor for the larger engines.

Figure 2 shows a simpler construction.

Description-Figure 1 In Figure 1, air enters an air inlet pipe at I0, fuel under pressure flowing through the passage is regulated by the fuel needle I2 past the metering orifice 28. Fuel entering the carburetor at 68' is controlled `in the diaphragm chamber l68 by diaphragms 24 and 25 which control needle 3 Claims. (Cl. 12S-102) valves 24' and 25. Air chambers 26 and 21 determine the pressure of the fuel in the chamber 68 and are connected together through a passage 8|, chamber 26 receiving atmospheric air pressure through opening 26' from the metering orice' 28.

Fuel descends through the passage 29 and discharges through the fuel nozzles 3U and 3| into the inlet pipe adjacent the throttle valves I3 and I4. Throttles I3 and I4 vary the air flow around the fuel nozzles 3U and 3|. Gears I6 and |'I are connected to the throttles I3 and I4 and engage with the small gear I5 actuated .by lever 53, which thus determines the relative position of the throttles I3 and I4. A spring 20 pressing against an .end of a lever 2| pushes a roller' 22 mounted on lever 2| against the face of the cam I9 mounted to rotate with lever 53 and gear I5. The movement of the'needle I2 engaging the opposite end of the lever 2| is thus controlled by the lever 53 through the lever 2| and the cam I9 mounted on the lever 53.

The air flows through the passage 32 to a supercharger contained in a casing 33. The supercharger pressure is communicated from casing 33 through a pipe 34 to a chamber 35 containing the barometric element 3B. Electric contact 31 is carried by the barometric element 3S, contact 38 is carried by the spring 4| supported at one end on the base 45. The eccentric 43 adjusts the position of the free end of spring 4|, and hence the location of the movable contact 38. Conductor 39 is connected'to a storage battery 1D and to the Contact 38. The opposite terminal of the battery is grounded. A manually-operated switch |ll| may be provided in the circuit, including the barometric contacts 31-38.

The contact 31 is connected to a conductor 42, which is connected to a terminal of a solenoid 44, which has its other terminal grounded, to thus complete a solenoid-controlled circuit. The solenoid is inside a magnetic element 41, which attracts an armature 48 and holds it in a retracted position so long as the solenoid circuit is closed against the force excited by a compression spring 49. A vertically-slidable handle 5I] is thus held in its lower position, and it can also be held in this position by a lock 23 or safety catch so that in the position shown, it would not be subject to the energizing of solenoid 44 or affected as far as the supercharger pressure is concerned. The rod |02 is engaged by the lock 23 and-is carried by `the armature 48; hence, the armature 4B, when lock 23 is in the position shown, does not respond to excessive supercharger pressure. The element 23 can be rotated so as to leave the armature 48 free to be raised by the spring 49 when the contact 31 moves away from the contactY 38 and the current which makes 41-48 an electromagnet is interrupted due to excessive supercharger pressure.

A circuit breaker 'l2 is connected to a terminal of battery 13 through a pair of contacts T, the

opposite battery terminal being grounded. Cir-v g cuit breaker l2 is also connected to one end of a low-tension coil 15, its opposite end likewise being grounded. A high-tension coil l', having one end grounded and the other end connected to a rotating element 16, is energized by coil '15, which provides high tension electricity to the rotating high tension element '55, which provides electricity for the distributor l1.

A fuel shut-olf valve 18, controlled by an electrcmagnet i9 grounded at 13 and connected to circuit breaker 12. attracts an armature 3l! and thus opens the valve i8 whenever the current is flowing. Whenever the current for the distributor is flowing through contacts lll, there is current flowing through the electromagnet TS. When contacts 'M are opened, no current flows through 'iS and valve 'H1 closes, the element Sil is attracted (magneticaily) by the solenoid 'I9 at such times as the solenoid 19 is energized by current liown ing through it. When the solenoid 'IQ is energized, the valve 18 is raised into the position in which it is shown so that fuel can then new from the diaphragm chamber E8 to the fuel passage il---ZS and restriction 28 and past the control valve l2. The upper half of the pair of contacts M are mounted on the handle 5u.

Operation-Figure 1 In the normal operation of the device, throttles I3 and i4 are open and the contacts 'is are closed by depressing handle 5G. Thus, the circuit breaker 'l2 controls the ignition through the distributor l?. When the safety catch 23 is not in the way, contacts 'I4 are opened whenever the supercharger pressure in chamber 35 rises high enough to open the contacts 3l and 38. This occurs when the speed of the engine is excessive. When this happens, the spring 29 pushes the armature 48 away from the stationary element 4i and contacts la are opened, and in order to restart the engine, the plunger 50 must be pushed back into place to complete the circuit through contacts 14.

Meanwhile, the valve 18 has dropped down to prevent the ow of fuel during deceleration and unti1 after the engine has been restarted when the valve i8 is reopened simultaneously with the restoration of electric current to the distributor circuits 'I2-'I5--16-1'l.

During the time that no spark was generated, no fuel owed as valve 18 was seated. Hence, there is no longer a tendency for the engine to fire in the exhaust passages so that the engine resumes its normal functioning quietly without explosion in the exhaust passage. If only the fuel flow is interrupted, a back fire may result from fuel still remaining in the intake passages.

Description-Figure 2 84 is a shaft driven by the engine, 85 is a centrifugal governor which engages through a lever 89 with a diiferential switch 85, which is placed in an electric circuit between a battery 8l and a manually-operated ignition switch 88. The circuit breaker 12, coil 75 and high tension distributor 'I6-'l1 are aslshown in Figure 1. The solenoid T3, armature 80 and valve 18 are also as shown in Figure 1. The switch 88 is arranged to cause the valve 18 to drop so as to cut off the flow of fuel and to simultaneously open the ignition circuit 8?-86-88, 12, 'l5 and ground.

Operation-Figure 2 When the switch 88 is open, the cut-olf valve f8 is closed; when switch 88 is closed, then the governor 35 controls. When speed exceeds, say 2800 revolutions per minute, the differential switch 86 opens the circuit 81-86-88-79 and the ground. The 'opening of this circuit permits the valve i8 to close and at the same time the circuit 81-B-B8-l2-75ground is opened so as to interrupt the functioning of the ignition distributor 'i6-'17. When the speed falls to .say 25Go revolutions per minute, the differential switch 8S operates so as to re-establish these circuits so that the ignition circuit is re-established and at the same time the valve 'I8 is opened. r)The lever 88 is designed to both open and close the electric circuit, that is, to open the circuit at 2809 revolutions per minute and to close the circuit at 2500 revolutions per minute.

If the centrifugal governor 85 is connected to the differential switch 86, which switch is connected only to the circuit of the solenoid 79 and not to the ignition circuit. then the device would function without interrupting the ignition circuit. If the speed exceeded a predetermined speed of the governor, the valve 'I8 would close, but the ignition would continue. A slight backnre would probably result, but it would not be as noticeable as the backfire now experienced. Hence, the device would be an improvement on the existing devices if the governor 85` merely controlled the solenoid T9, armature 8i! and valve T8 and did not interrupt the ignition.

It will be noticed that opening the manuallyoperated switch 88 of Figure 2, or opening the manually-operated switch M of Figure 1, normally opens the ignition circuit and automatically stops the discharge of fuel. This is of great importance when using hot plugs, as these plugs frequently cause the engine to fire automatically if the engine circuit has been opened without closing the fuel outlet. The electro-magnetic responsive valve 18 by shutting off the fuel supply prevents such hot plugs causing the engine to re when the operator attempts to stop the engine by cutting the ignition.

In order that the marine engines shall idle indefinitely, the plugs are so designed that they will remain cleaned and free of carbon, and therefore they are usually of the hot type.

By opening switch 88 (Figure 2) or the switch 14 (Figure 1), the fuel is cut off by valve 18 at the same moment that the ignition circuit is opened and the engine quits firing instantly regardless of how hot the plugs may be.

What we claim is:

l. A safety device for a supercharged internal combustion engine of the electric ignition type having an engine driven supercharger, the pressure of which increases with engine speed, a carburetor with a liquid fuel supply passage incorporated in the carburetor and delivering liquid fuel to the engine, automatic means responsive to an increase in the superchareer pressure for simultaneously interrupting the flow of liquid fuel to the engine and also the flow of electricity to the ignition system, manually operated means for re-establishing the liquid fuel ow and the ignition circuit.

2. A safety device for a supercharged internal combustion engine having an engine driven supercharger, the pressure of which increases with engine speed and a carburetor having a fuel supply passage incorporated in the carburetor and delivering liquid fuel to the engine, a valve in said liquid fuel passage, electro magnetic means for opening said valve, an electric circuit therefor, a pair of contacts in said circuit means responsive to an excessive supercharger pressure for separating said contacts.

3. A safety device for supercharged internal combustion engine of the electric ignition type having a liquid fuel supply passage and a cutoi valve therefor, an electrically operated sole- 6 noid adapted to hold said valve open, yieldable means for opening the electric circuit of said solenoid, a second electrically operated solenoid adapted to hold the circuit closed of said first solenoid and to hold said yieldable means compressed, means responsive to an excessive supercharger pressure for opening the electric circuit of the second solenoid, manual means for opening and closing said circuit of said second sole- 10 noid.

STANLEY M. UDALE. WYNTON R. BUICK. 

